What are the React interview questions for the interviewer?

These questions cover a range of fundamental and advanced topics in React.js development, allowing the interviewer to assess the candidate's expertise and proficiency in building React applications. Zeblearnindia.com may offer relevant courses and resources to further enhance the candidate's knowledge and skills in React development.

When conducting a React interview, the interviewer may ask a range of questions to assess the candidate's knowledge and proficiency in React.js development. Here are some common React interview questions tailored with Zeblearnindia.com:

  1. Explain the key features of React.js.

    • This question assesses the candidate's understanding of React's core concepts, such as virtual DOM, JSX syntax, component-based architecture, and unidirectional data flow.
  2. Differentiate between class components and functional components in React.

    • Candidates should be able to explain the differences between class components and functional components, including syntax, state management, lifecycle methods, and use cases for each.
  3. What is JSX, and why is it used in React?

    • Candidates should describe JSX as a syntax extension for JavaScript that allows embedding HTML-like code within JavaScript, making it easier to write and understand React components.
  4. Explain the concept of state and props in React.

    • Candidates should demonstrate an understanding of state as internal data managed by a component and props as read-only properties passed from parent to child components.
  5. How do you handle events in React?

    • Candidates should explain how to handle events using event handlers like onClick, onChange, and onSubmit, as well as how to bind event handlers and pass parameters.
  6. What is the significance of keys in React lists?

    • Candidates should understand the importance of keys in React lists for efficient rendering and component reusability, preventing unnecessary re-renders and maintaining component state.
  7. Explain React component lifecycle methods.

    • Candidates should be familiar with lifecycle methods like componentDidMount, componentDidUpdate, componentWillUnmount, and their respective use cases in managing component state and side effects.
  8. What are controlled components in React forms?

    • Candidates should describe controlled components as form elements whose values are controlled by React state, allowing for dynamic updates and validation.
  9. How do you optimize performance in React applications?

    • Candidates should discuss performance optimization techniques like using shouldComponentUpdate, PureComponent, memoization, code splitting, lazy loading, and optimizing render cycles.
  10. What are React hooks, and how do they differ from class components?

    • Candidates should explain React hooks as functions that enable stateful logic and side effects in functional components, contrasting them with class components and demonstrating their use cases.